You have watched "Star Wars" thousands of times, know a decent amount of Klingon and built the TARDIS from "Doctor Who" in your backyard. But nothing quite expresses an obsessive love of science fiction like quirky gadgets. Ready to spend on some geeky gifts? Engage!

R2-D2 USB Car Charger - Drivers are going to want a fully charged cellphone for long road trips to the Dagobah system. It features two USB ports and — most importantly — its head swivels as it makes classic R2-D2 beeping sounds. ($39.99)
Star Trek Borg Cube Fridge - Assimilate some Mountain Dew with this mini-fridge that glows green inside, just like the Borg cubes from "Star Trek: The Next Generation." Sorry thirst; resistance is futile. ($149.99)

Doctor Who: Sonic Screwdriver - There are plenty of beeping, blinking replicas of the Doctor's most famous tool. But this sonic screwdriver actually functions as a normal screwdriver with interchangeable bits. ($49.98)
Personalized Superhero Action Figures - Sometimes fan fiction just isn't enough. Take two pictures of your face, and you can get a personalized 3-D-printed head for a Marvel or DC superhero's body. Warning: Product does not come with explanation to mother or significant other. ($130.95)
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